Electronic Controls
The FuelMizer® (SR501-OR) is a microprocessor-based control designed to regulate the supply water temperature of a single boiler, based on the outdoor temperature. The FuelMizer is a boiler reset control and switching relay in one unit; it is ideal for retrofit application, but may also be used in new installations as well.
Savings from 5% to 30% $900 $800
Savings
$700 $600 $500
Savings Range
$400 $300 $200 $100 $0
$0
$1000
$2000
$3000
$4000
Yearly Amount Spent on Fuel
©Taco Catalog #100-100 Supersedes: 06/12/12
Effective Date: 04/07/14 Printed in USA
SR 501O
AMP
INPUT 120 VAC
ZONE 1 120 VAC
N H N H
Instruction Sheet # 102-420 Supersedes: 06/12/12
Submittal Data Information FuelMizer®
Effective: 04/07/14
N
POWER INPUT (120 VAC)
SYSTEM CIRCULATOR (OPTIONAL)
H
ONE ZONE INSTALLATION W/O INDIRECT DHW
Application
The FuelMizer (SR501-OR) includes functions such as automatic reset ratio calculation, warm weather shut down (WWSD), minimum boiler temperature setting, and boiler differential setting. The control also includes both boiler and outdoor sensors. 24 VAC THERMOSTAT
DESIGN OUTDOOR TEMPERATURE FOR 180°F SUPPLY TEMPERATURE -10 0 10 -20 20 POT1 -30 30
OFF
X X R W C R W OUTDOOR BOILER
Boiler ..................... Minimum: ...........70°F or 140°F ...................................(21°C or 60°C)
TSTAT
SENSOR
DHW
ONE ZONE SWITCHING RELAY WITH OUTDOOR RESET
40
FUSE 5 AMP
POWER IN 24 VAC
LED INDICATORS
POWER
24 VAC ZONE VALVES PUMP END SWITCH
X
X
ZONE 1 1 2 3 4
ZONE 3 PUMP END SWITCH
N/O COM N/C
2 WIRE ZONE VALVE (NO END SWITCH) MUST USE JUMPER
BOILER SUPPLY SENSOR
T STAT 1
VALVE 1
T STAT 2
VALVE 2
T STAT 3
VALVE 3
PRIORITY
ZONE 2 1 2 3 4
ZONE 3 1 2 3 4
1 2 3
1 2 3
TACO 3 WIRE ZONE VALVE
TACO 3 WIRE ZONE VALVE
OUTDOOR SENSOR BOILER SUPPLY SENSOR
SW1
SUPPLY SENSOR
DESIGN OUTDOOR TEMPERATURE FOR 180°F SUPPLY TEMPERATURE -10 0 10 -20 20 POT1 -30 30
LED INDICATORS
OFF
40
X X R W C R W OUTDOOR BOILER
TSTAT
DHW
SR 501OR-4
INPUT 120 VAC
TSTAT
TSTAT DHW OVERRIDE BOILER RELAY
ZONE 1 120 VAC
N H N H POWER INPUT (120 VAC)
SYSTEM CIRCULATOR (OPTIONAL)
H
CONFIGURATION OUTDOOR DIP SWITCHES TEMPERATURE CONTROL ADJUSTMENT
A
DHW AQUASTAT
SENSOR CONNECTIONS
ZONE 3 PRIORITY
R W C R W C R W C ZONE 1 ZONE 2 ZONE 3 THERMOSTATS PRIORITY
SYSTEM CIRCULATOR (OPTIONAL)
DEMAND INPUT CONNECTIONS
BOILER CONTROL CONNECTIONS
THERMOSTATS (24VAC)
N H
MULTI-ZONE INSTALLATION WITH ZONE CONTROL, WITH INDIRECT DHW
ONE ZONE INSTALLATION W/O INDIRECT DHW
X X ISOLATED END SWITCH
6 AMP
INPUT 120 VAC
ZONE 1 120 VAC
N
POWER IN 24 VAC
LED INDICATORS POWER
N H N H POWER INPUT (120 VAC)
SUPPLY SENSOR
POWER
BOILER RELAY
6 AMP
SENSOR
ONE ZONE SWITCHING RELAY WITH OUTDOOR RESET
DHW OVERRIDE
ON OFF
LED INDICATORS
POWER
EXISTING ZONE VALVE CONTROL
24 VAC ZONE VALVES PUMP END SWITCH
X
X
ZONE 1 1 2 3 4
ZONE 3 PUMP END SWITCH
N/O COM N/C
BOILER CONTROL
1 2 3
TACO 3 WIRE ZONE VALVE
T STAT 1
VALVE 1
T STAT 2
VALVE 2
T STAT 3
VALVE 3
ZONE 3 1 2 3 4
1 2 3
TACO 3 WIRE ZONE VALVE
OUTDOOR SENSOR BOILER SUPPLY SENSOR
OFF ON
SW1
DESIGN OUTDOOR TEMPERATURE FOR 180°F SUPPLY TEMPERATURE -10 0 10 -20 20 POT1 -30 30
OFF
40
X X R W C R W OUTDOOR BOILER
TSTAT
DHW
SENSOR
ONE ZONE SWITCHING RELAY WITH OUTDOOR RESET
SUPPLY SENSOR
LED INDICATORS POWER TSTAT
SR 501OR-4
DHW OVERRIDE 6 AMP
INPUT 120 VAC
BOILER RELAY
ZONE 1 120 VAC
N H N H N INPUT TRANSFORMER (120 VAC) H POWER
EXTERNAL DIAGNOSTIC LED'S
PRIORITY
ZONE 2 1 2 3 4
JUMPER 3&4 2 WIRE ZONE VALVE (NO END SWITCH) MUST USE JUMPER
...................................(25°C ±0.2°C) ...................................ß=3892 Outdoor ............... Design Temp.: ..-30°F to 40°F ...................................(-35°C to 5°C)
OFF
SW1
Relays: ...................Boiler Relay ...................................1 amp @ 24 VAC
Sensors: ................NTC thermistor, ...................................10 kΩ @ 77°F
ON
EXISTING ZONE VALVE CONTROL
BOILER CONTROL
Power Supply:...120/60/1 VAC, ...................................12 amps maximum
Thermostat: .......24 VAC ...................................Class 2 Output
R W C R W C R W C ZONE 1 ZONE 2 ZONE 3 THERMOSTATS PRIORITY
OFF ON
Enclosure: ...........TYPE 1
...................................Circulator Relay ...................................1⁄3 HP ...................................(6 FLA, 36 LRA)
DHW AQUASTAT
ZONE 3 PRIORITY
X X ISOLATED END SWITCH
OFF ON
Control: ................Microprocessor ...................................control. This is ....................... not a safety ....................... (limit)control.
Approvals: ..........UL listed for ...................................US and Canada, ...................................Temperature ...................................Indicating ...................................and Regulating ...................................Equipment.
A
JUMPER 3&4
OUTDOOR SENSOR
BOILER CONTROL
Specifications
Dimensions: ......4-1⁄4" W x 5-1⁄4" H ...................................x 2-3⁄4" D
THERMOSTATS (24VAC)
SR 501OR-4
• Full outdoor boiler reset control • Can control system or zone valve circulator • Over-ride of outdoor reset when DHW tank is calling • Easy to install and set; will not affect boiler’s warranty • Front mounted LED lights for full diagnostic information • Ideal for retrofit applications of just about any hot water boiler • Typical energy savings is about 14% with some customers experiencing up to 30%
FUSE 5 AMP
Features
POWER INPUT SYSTEM CIRCULATOR CONNECTIONS CIRCULATOR OUTPUT (OPTIONAL) CONNECTIONS
The installer must ensure that this control and its wiring are isolated and/or shielded from strong sources of electromagnetic noise. This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. FUSE
MULTI-ZONE INSTALLATION WITH ZONE CONTROL, WITH INDIRECT DHW
Differential: ........10°F or 20°F ...................................(6°C or 12°C) WWSD: .................70°F (21°C) Taco Inc., 1160 Cranston Street, Cranston, RI 02920 / (401) 942-8000 / Fax (401) 942-2360 Taco (Canada) Ltd., 8450 Lawson Road, Unit #3, Milton, Ontario L9T 0J8 / (905) 564-9422 / Fax (905) 564-9436 www.TacoComfort.com
